JP2005156592A - Illumination optical device, exposure device and exposure method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To realize suitable illumination conditions required for faithfully transferring a mask pattern having various characteristics, for instance, illumination conditions having a variety as to the light intensity distribution of a secondary light source, a polarization state and so on. <P>SOLUTION: An illuminating optical device for illuminating a surface (M) to be irradiated is provided with illumination pupil forming means (3, 4, 7, 8) for forming illumination pupil distribution having light intensity distribution located in a center area including an optical axis (AX) and light intensity distribution located in a plurality of peripheral areas separated from the optical axis (AX), with intervals on the pupil surface of the illuminating optical device or its vicinity and area changing means (6: 6a, 6b) for changing the positions and the sizes of the light intensity distribution located in the plurality of peripheral areas, independently of the light intensity distribution located at the center area. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an illumination optical apparatus, an exposure apparatus, and an exposure method, and more particularly to an exposure apparatus for manufacturing a microdevice such as a semiconductor element, an imaging element, a liquid crystal display element, and a thin film magnetic head in a lithography process.

  In a typical exposure apparatus of this type, a light beam emitted from a light source passes through a fly-eye lens (or microlens array) as an optical integrator, and a secondary light source as a substantial surface light source composed of a number of light sources. A light source (generally a predetermined light intensity distribution on the illumination pupil plane) is formed. The light beam from the secondary light source is limited through an aperture stop disposed in the vicinity of the rear focal plane of the fly-eye lens, and then enters the condenser lens.

  The light beam condensed by the condenser lens illuminates the mask on which a predetermined pattern is formed in a superimposed manner. The light transmitted through the mask pattern forms an image on the wafer via the projection optical system. Thus, the mask pattern is projected and exposed (transferred) onto the wafer. The pattern formed on the mask is highly integrated, and it is essential to obtain a uniform illuminance distribution on the wafer in order to accurately transfer this fine pattern onto the wafer.

  Therefore, a circular secondary light source is formed on the rear focal plane of the fly-eye lens, and the size thereof is changed to change the illumination coherency σ (σ value = aperture aperture diameter / projection optical system pupil diameter, or σ Attention has been focused on a technique of changing the value = the exit numerical aperture of the illumination optical system / the incident numerical aperture of the projection optical system. Further, attention has been focused on a technique for forming an annular or quadrupolar secondary light source on the rear focal plane of the fly-eye lens to improve the depth of focus and resolution of the projection optical system.

  In the conventional exposure apparatus as described above, normal circular illumination based on a circular secondary light source is performed according to the pattern characteristics of the mask, or modified illumination based on a ring-shaped or quadrupolar secondary light source (ring Band lighting and quadrupole lighting). However, appropriate illumination conditions necessary for faithfully transferring a mask pattern having various characteristics, for example, illumination conditions rich in diversity regarding the light intensity distribution and polarization state of the secondary light source cannot be realized. It was.

  The present invention has been made in view of the above-described problems. For example, when mounted on an exposure apparatus, an appropriate illumination condition necessary for faithfully transferring a mask pattern having various characteristics, such as a secondary illumination. It is an object of the present invention to provide an illumination optical device that can realize a wide variety of illumination conditions regarding the light intensity distribution and polarization state of a light source. Further, the present invention has been realized according to the pattern characteristics of the mask, using an illumination optical device that can realize appropriate illumination conditions necessary for faithfully transferring a mask pattern having various characteristics, for example. An object of the present invention is to provide an exposure apparatus and an exposure method capable of performing good exposure under appropriate illumination conditions.

In order to solve the above problems, in the first embodiment of the present invention, in the illumination optical device that illuminates the illuminated surface,
An illumination pupil distribution having a light intensity distribution located in a central region including an optical axis and a light intensity distribution located in a plurality of peripheral regions spaced from the optical axis on or near the pupil plane of the illumination optical device. Illumination pupil forming means for forming;
Illumination optics comprising: area changing means for changing the position and size of the light intensity distribution located in the plurality of peripheral areas independently of the light intensity distribution located in the central area. Providing equipment.

  According to a preferred aspect of the first aspect, the illumination pupil forming means converts the incident light beam into a central light beam corresponding to the central region and a plurality of peripheral light beams respectively corresponding to the plurality of peripheral regions. A light beam conversion element for entering the changing means is provided. The region changing means includes a first prism having a refracting surface having a concave cross section, and a second prism having a refracting surface having a convex cross section formed substantially complementary to the refractive surface of the concave section of the first prism. Preferably, the distance between the first prism and the second prism is variably configured, and the refracting surface has a flat central portion substantially orthogonal to the optical axis.

  In this case, it is preferable that the refracting surface has the central portion and a peripheral conical portion corresponding to a side surface of the conical body centered on the optical axis. In this case, it is preferable that the peripheral cone portion has one peripheral cone portion corresponding to a side surface of the single cone centered on the optical axis. Alternatively, the peripheral cone portion has an inner peripheral cone portion corresponding to a side surface of the first cone centered on the optical axis, and a first apex angle centered on the optical axis and smaller than that of the first cone body. It is preferable to have an outer peripheral cone corresponding to the side of the two cones. In the first embodiment, it is preferable that the region changing means has a plurality of replaceable pairs of the first prism and the second prism, and the area of the central portion is different for each set.

In the second embodiment of the present invention, in the illumination optical device that illuminates the illuminated surface,
Illumination pupil forming means for forming an illumination pupil distribution having a light intensity distribution located in the first region and a light intensity distribution located in the second region on or near the pupil plane of the illumination optical device;
An illumination optical apparatus comprising: a polarization setting unit configured to set a light beam passing through the first region to a non-polarized state and set a light beam passing through the second region to a polarization state. provide.

  According to a preferred aspect of the second aspect, the first region has a central region including an optical axis, and the second region has a peripheral region spaced from the optical axis. In this case, the second region has two peripheral regions arranged substantially symmetrically with respect to the optical axis along the first direction, and the polarization setting means is configured to polarize a light beam passing through the two peripheral regions. It is preferable to set the state to a linearly polarized state having a polarization plane in a direction substantially orthogonal to the first direction. Alternatively, the second region is arranged in four positions arranged at the vertices of each rectangular quadrilateral having a side along the first direction and a side along the second direction substantially orthogonal to the first direction. Preferably, the polarization setting means sets a polarization state of a light beam passing through the four peripheral regions to a linear polarization state having a polarization plane in the first direction or the second direction.

  Alternatively, in the second mode, the second region is located at the position of each vertex of a rectangular quadrilateral having a side along the first direction and a side along the second direction substantially orthogonal to the first direction. The polarization setting means has a polarization state of a light beam passing through the four peripheral areas in a direction that forms an angle of approximately 45 degrees with the first direction or the second direction. It is preferable to set a linear polarization state having a polarization plane. In this case, the polarization setting means sets the polarization state of the light beam passing through one pair of peripheral regions facing each other across the optical axis among the four peripheral regions at an angle of approximately 45 degrees with the first direction. Is set to a linear polarization state having a polarization plane in the third direction, and the polarization state of the light beam passing through the other pair of peripheral regions facing each other across the optical axis is approximately 45 degrees with respect to the first direction. It is preferable to set the linear polarization state having an angle and a polarization plane in a fourth direction substantially orthogonal to the third direction.

  Alternatively, in the second form, the second region is a vertex of each rectangular first quadrilateral having a side along the first direction and a side along the second direction substantially orthogonal to the first direction. Each of a rectangular second quadrangle having four inner peripheral regions arranged at positions, a side along the first direction and a side along the second direction, and surrounding the first quadrangle Four outer peripheral regions arranged at the positions of the vertices, and the polarization setting means is configured to change the polarization state of the light beam passing through the four inner peripheral regions in the first direction or the second direction. It is preferable to set the polarization state of the light beam passing through the four outer peripheral regions to the linear polarization state having a polarization plane in the second direction or the first direction.

  Alternatively, in the second form, the second region is a vertex of each rectangular first quadrilateral having a side along the first direction and a side along the second direction substantially orthogonal to the first direction. Each of a rectangular second quadrangle having four inner peripheral regions arranged at positions, a side along the first direction and a side along the second direction, and surrounding the first quadrangle Four outer peripheral regions arranged at the positions of the vertices, and the polarization setting means sets the polarization state of the light beam passing through the four inner peripheral regions and the four outer peripheral regions to the first direction. It is preferable to set a linear polarization state having a polarization plane in a direction that forms an angle of approximately 45 degrees.

  Further, according to a preferred aspect of the second mode, the polarization setting means has a depolarizing element for depolarizing the linearly polarized light beam traveling toward the first region as necessary. The polarization setting means preferably has a phase member for changing the polarization plane of the linearly polarized light beam traveling toward the second region as necessary. The polarization setting means preferably further includes a second phase member for changing the incident elliptically polarized light into linearly polarized light having a polarization plane in a predetermined direction. Moreover, it is preferable to further comprise area changing means for changing the positions and sizes of the plurality of peripheral areas independently of the central area. In this case, the illumination pupil forming means converts the incident light flux into a central light flux directed to the central area and a plurality of peripheral light fluxes directed to the plurality of peripheral areas, and enters the area changing means. It is preferable to have an element.

  Further, according to a preferred aspect of the second embodiment, the region changing means includes a first prism having a refracting surface having a concave cross section, and a convex formed substantially complementary to the refracting surface having the concave cross section of the first prism. A second prism having a refracting surface having a cross-section, the interval between the first prism and the second prism being variably configured, and the refracting surface being a flat central portion substantially orthogonal to the optical axis Have In this case, it is preferable that the refracting surface has the central portion and a peripheral conical portion corresponding to a side surface of the conical body centered on the optical axis. In this case, it is preferable that the peripheral cone portion has one peripheral cone portion corresponding to a side surface of the single cone centered on the optical axis. Alternatively, the peripheral cone portion has an inner peripheral cone portion corresponding to a side surface of the first cone centered on the optical axis, and a first apex angle centered on the optical axis and smaller than that of the first cone body. It is preferable to have an outer peripheral cone corresponding to the side of the two cones. Further, it is preferable that the area changing unit has a plurality of exchangeable pairs of the first prism and the second prism, and the area of the central portion is different for each set.

In the third embodiment of the present invention, in the illumination optical device that illuminates the illuminated surface,
Illumination pupil forming means for forming an illumination pupil distribution having a light intensity distribution located in the first region and a light intensity distribution located in the second region on or near the pupil plane of the illumination optical device;
An illumination optical apparatus comprising: a polarization state changing unit for changing a polarization state of the light beam passing through the second region independently of a polarization state of the light beam passing through the first region. provide.

  According to a preferred aspect of the third aspect, the first region has a central region including an optical axis, and the second region has a peripheral region spaced from the optical axis. Further, it is preferable that the polarization state changing unit changes the state of the light beam passing through the first region between a non-polarized state and a linearly polarized state. The polarization state changing unit preferably changes the state of the light beam passing through the second region between two linear polarization states having polarization planes in different directions. Moreover, it is preferable that the polarization state changing unit has a depolarizing element for depolarizing the linearly polarized light beam traveling toward the first region as necessary. In this case, it is preferable that the depolarizing element is configured to be removable from the optical path.

  Further, according to a preferred aspect of the third mode, the polarization state changing means has a phase member for changing the polarization plane of the linearly polarized light beam toward the second region as necessary. Preferably, the polarization state changing means further includes a second phase member for changing the incident elliptically polarized light into linearly polarized light having a polarization plane in a predetermined direction. Moreover, it is preferable to further comprise area changing means for changing the positions and sizes of the plurality of peripheral areas independently of the central area. In this case, the illumination pupil forming means converts the incident light beam into a central light beam directed to the central region and a plurality of peripheral light beams directed to the plurality of peripheral regions, and enters the region changing device. It is preferable to have an element.

  Further, according to a preferred aspect of the third aspect, the region changing means includes a first prism having a refracting surface having a concave cross section, and a convex formed substantially complementary to the refracting surface having the concave cross section of the first prism. A second prism having a refracting surface having a cross-section, the interval between the first prism and the second prism being variably configured, and the refracting surface being a flat central portion substantially orthogonal to the optical axis Have In this case, it is preferable that the refracting surface has the central portion and a peripheral conical portion corresponding to a side surface of the conical body centered on the optical axis. In this case, it is preferable that the peripheral cone portion has one peripheral cone portion corresponding to a side surface of the single cone centered on the optical axis. Alternatively, the peripheral cone portion has an inner peripheral cone portion corresponding to a side surface of the first cone centered on the optical axis, and a first apex angle centered on the optical axis and smaller than that of the first cone body. It is preferable to have an outer peripheral cone corresponding to the side of the two cones. Further, it is preferable that the area changing unit has a plurality of exchangeable pairs of the first prism and the second prism, and the area of the central portion is different for each set.

In the fourth aspect of the present invention, in the illumination optical device that illuminates the illuminated surface,
Illumination pupil forming means for forming a light intensity distribution located in a ring-shaped region having the optical axis substantially in the center on or near the pupil plane of the illumination optical device,
The ring-shaped region has a plurality of regions along a circumferential direction of a circle substantially centered on the optical axis,
The polarization state of a plurality of light fluxes passing through each of the plurality of regions of the annular zone is set to a linear polarization state having a polarization plane along a direction substantially in contact with the circle at substantially the center of each of the plurality of regions. An illumination optical device is provided, further comprising a polarization setting unit.

  According to a preferred aspect of the fourth aspect, the polarization setting means has a plurality of phase members arranged to correspond to the plurality of regions, and each phase member has a polarization plane of incident linearly polarized light. Change as needed.

  According to a fifth aspect of the present invention, there is provided an exposure apparatus comprising the illumination optical apparatus according to the first to fourth aspects for illuminating a mask, and exposing the pattern of the mask onto a photosensitive substrate. . In this case, the image forming apparatus further includes a projection optical system for forming an image of the mask pattern on the photosensitive substrate, and the pupil plane of the illumination optical device is positioned substantially conjugate with the pupil position of the projection optical system. Preferably it is.

In the sixth embodiment of the present invention, an illumination step of illuminating the mask using the illumination optical devices of the first to fourth embodiments,
And an exposure step of exposing the pattern of the mask onto a photosensitive substrate. In this case, the exposure step includes a projection step of forming an image of the mask pattern on the photosensitive substrate using a projection optical system, and the pupil plane of the illumination optical device is a pupil position of the projection optical system. It is preferable that it is positioned almost conjugate with.

  In the illumination optical apparatus of the present invention, for example, the position and magnitude of the light intensity distribution formed in the pupil plane or in the vicinity thereof and located in a plurality of peripheral regions spaced from the optical axis by the action of the region changing means including a prism pair. Can be changed independently of the light intensity distribution located in the central region including the optical axis. Further, for example, the light beam passing through the first region as the central region including the optical axis is set to the non-polarized state by the action of the polarization setting means including the half-wave plate and the declination prism assembly, and the optical axis Can be set in a linearly polarized state (generally a polarization state). Further, the polarization of the light beam passing through the second region as one or a plurality of peripheral regions spaced from the optical axis by the action of the polarization state changing means comprising, for example, a half-wave plate and a declination prism assembly. The state can be changed independently of the polarization state of the light beam passing through the first region as the central region including the optical axis.

  Therefore, for example, when the illumination optical apparatus of the present invention is mounted on an exposure apparatus, appropriate illumination conditions necessary for faithfully transferring a mask pattern having various characteristics, such as the light intensity distribution and polarization state of a secondary light source, etc. A variety of lighting conditions can be realized. In addition, in the exposure apparatus and exposure method using the illumination optical apparatus of the present invention, it is possible to realize appropriate illumination conditions necessary for faithfully transferring a mask pattern having various characteristics. Accordingly, it is possible to perform good exposure under appropriate illumination conditions realized accordingly, and thus it is possible to manufacture a good device with high throughput.

Embodiments of the present invention will be described with reference to the accompanying drawings.
FIG. 1 is a view schematically showing a configuration of an exposure apparatus including an illumination optical apparatus according to the first embodiment of the present invention. In FIG. 1, the Z axis along the normal direction of the wafer W, which is a photosensitive substrate, the Y axis in the direction parallel to the plane of FIG. 1 in the plane of the wafer W, and the plane of the wafer W in FIG. The X axis is set in the direction perpendicular to the paper surface. The exposure apparatus of the first embodiment includes a light source 1 for supplying exposure light (illumination light).

  As the light source 1, for example, a KrF excimer laser light source that supplies light with a wavelength of 248 nm, an ArF excimer laser light source that supplies light with a wavelength of 193 nm, or the like can be used. A substantially parallel light beam emitted from the light source 1 along the Z direction has a rectangular cross section extending along the X direction and is incident on a beam expander 2 including a pair of lenses. Each lens has a negative refractive power and a positive refractive power in the plane of FIG. 1 (in the YZ plane). Accordingly, the light beam incident on the beam expander 2 is enlarged in the plane of FIG. 1 and shaped into a light beam having a predetermined rectangular cross section.

  A substantially parallel light beam via a beam expander 2 as a shaping optical system is deflected in the Y direction by a bending mirror and then enters an afocal lens (relay optical system) 4 via a diffractive optical element 3. In general, a diffractive optical element is formed by forming a step having a pitch of the wavelength of exposure light (illumination light) on a substrate, and has a function of diffracting an incident beam to a desired angle. Specifically, the diffractive optical element 3 has, for example, a circular light intensity centered on the optical axis AX in the far field (or Fraunhofer diffraction region) when a parallel light beam having a rectangular cross section is incident. It has a function of forming three circular light intensity distributions consisting of the distribution and two circular light intensity distributions spaced in the Z direction with the optical axis AX as the center.

  On the other hand, the afocal lens 4 is set so that the front focal position thereof and the position of the diffractive optical element 3 substantially coincide with each other, and the rear focal position thereof substantially coincides with the position of the predetermined surface 5 indicated by a broken line in the drawing. It is an afocal system (afocal optical system). Therefore, the substantially parallel light beam incident on the diffractive optical element 3 forms three circular light intensity distributions on the pupil plane of the afocal lens 4 and then exits from the afocal lens 4 as a substantially parallel light beam. In addition, in the optical path between the front lens group 4a and the rear lens group 4b of the afocal lens 4, a prism pair 6 as an axicon system is disposed at or near the pupil. The operation will be described later.

  The diffractive optical element 3 is configured to be detachable with respect to the illumination optical path, and is configured to be exchangeable with another diffractive optical element that forms a different light intensity distribution in the far field. Similarly, the prism pair 6 is configured to be detachable with respect to the illumination optical path, and is configured to be exchangeable with other prism pairs having different configurations and functions. Hereinafter, in order to simplify the description, the basic configuration and operation of the first embodiment will be described ignoring the operation of the prism pair 6. The light beam that has passed through the afocal lens 4 enters a microlens array 8 through a zoom lens (variable magnification optical system) 7.

  Here, the position of the predetermined surface 6 is disposed in the vicinity of the front focal position of the zoom lens 7, and the incident surface of the microlens array 8 is disposed in the vicinity of the rear focal position of the zoom lens 7. In other words, the zoom lens 7 arranges the predetermined surface 6 and the incident surface of the microlens array 8 in a substantially Fourier-transformed relationship, so that the pupil surface of the afocal lens 4 and the incident surface of the microlens array 8 are arranged. Optically arranged in a conjugate manner. Therefore, on the incident surface of the microlens array 8, like the pupil surface of the afocal lens 4, a circular illumination field centered on the optical axis AX and an interval in the Z direction centered on the optical axis AX are spaced apart. Three circular illuminating fields composed of two circular illuminating fields are formed. The overall shape of the three circular illumination fields changes in a similar manner depending on the focal length of the zoom lens 7.

  The microlens array 8 is an optical element composed of a large number of microlenses having positive refracting power that are arranged vertically and horizontally and densely. In general, a microlens array is configured by forming a group of microlenses by etching a plane parallel plate, for example. Here, each microlens constituting the microlens array is smaller than each lens element constituting the fly-eye lens. Further, unlike a fly-eye lens composed of lens elements isolated from each other, the microlens array is formed integrally with a large number of microlenses (microrefractive surfaces) without being isolated from each other. However, the microlens array is an optical integrator of the same wavefront division type as that of the fly-eye lens in that lens elements having positive refractive power are arranged vertically and horizontally.

  Each microlens constituting the microlens array 8 has a rectangular cross section similar to the shape of the illumination field to be formed on the mask M (and thus the shape of the exposure region to be formed on the wafer W). A light beam incident on the microlens array 8 is two-dimensionally divided by a large number of microlenses, and an illumination formed by the light beam incident on the microlens array 8 on the rear focal plane (and hence the illumination pupil plane or its vicinity). A secondary light source having substantially the same light intensity distribution as the field, as shown in FIG. 2A, a circular light intensity distribution (substantially surface light source) 30a centered on the optical axis AX and the optical axis AX. As a result, a Z-direction tripolar secondary light source composed of two circular light intensity distributions (substantially surface light sources) 30b spaced apart in the Z direction is formed.

  A light beam from a Z-direction tripolar secondary light source (generally a predetermined light intensity distribution formed on or near the pupil plane of the illumination optical device) formed on the rear focal plane of the microlens array 8 is After passing through the condenser optical system 9, the mask blind 10 is illuminated in a superimposed manner. Thus, a rectangular illumination field corresponding to the shape and focal length of each microlens constituting the microlens array 8 is formed on the mask blind 10 as an illumination field stop. The light flux that has passed through the rectangular opening (light transmitting portion) of the mask blind 10 receives the light condensing action of the imaging optical system 11 and then illuminates the mask M on which a predetermined pattern is formed in a superimposed manner.

  Thus, the imaging optical system 11 forms an image of the rectangular opening of the mask blind 10 on the mask M. The light beam that has passed through the pattern of the mask M forms an image of the mask pattern on the wafer W, which is a photosensitive substrate, via the projection optical system PL. Thus, by performing batch exposure or scan exposure while driving and controlling the wafer W two-dimensionally in a plane (XY plane) orthogonal to the optical axis AX of the projection optical system PL, each exposure region of the wafer W is masked. M patterns are sequentially exposed.

  As described above, the diffractive optical element 3, the afocal lens 4, the zoom lens 7, and the microlens array 8 are located in the central region including the optical axis AX on or near the pupil plane of the illumination optical device (1-11). Light intensity distribution, that is, a circular surface light source 30a centered on the optical axis AX, and light intensity distributions located in a plurality of peripheral areas spaced from the optical axis AX, that is, the optical axis AX is spaced in the Z direction. Illumination pupil forming means for forming an illumination pupil distribution having two circular surface light sources 30b separated from each other is configured. In addition, the diffractive optical element 3 is configured so that an incident light beam is divided into two circular shapes with a center light beam corresponding to the circular surface light source 30a centered on the optical axis AX and an interval in the Z direction centered on the optical axis AX. A light beam conversion element for converting into a plurality of peripheral light beams respectively corresponding to the surface light source 30b is configured.

  FIG. 3 is a diagram schematically showing the configuration and operation of a prism pair arranged in the optical path between the front lens group and the rear lens group of the afocal lens. As shown in FIG. 3, the prism pair 6 includes, in order from the light source side, a first prism member 6a having a flat surface facing the light source side and a refractive surface having a concave cross section facing the mask side; And a second prism member 6b having a refracting surface having a convex cross section on the side. The concave refracting surface of the first prism member 6a and the convex refracting surface of the second prism member 6b are complementarily formed so as to be in contact with each other.

  More specifically, the refracting surface of the concave section of the first prism member 6a has a planar central portion 6c orthogonal to the optical axis AX and a peripheral cone portion corresponding to the side surface of the cone centered on the optical axis AX. 6d. Similarly, the refracting surface of the convex section of the second prism member 6b has a planar central portion 6e orthogonal to the optical axis AX, and a peripheral conical portion 6f corresponding to the side surface of the cone centered on the optical axis AX. Have In addition, at least one member of the first prism member 6a and the second prism member 6b is configured to be movable along the optical axis AX, and the concave surface of the first prism member 6a has a refracting surface and the second prism member 6b. The interval between the convex cross section and the refractive surface is variable.

  In the prism pair 6, as shown in FIG. 3, a central light beam 31a that forms a circular center surface light source 30a centered on the optical axis AX among the Z direction tripolar secondary light sources is a first prism member 6a. Passes through the central portion 6c and the central portion 6e of the second prism member 6b. On the other hand, of the Z direction tripolar secondary light sources, two peripheral luminous fluxes 31b forming two circular peripheral surface light sources 30b spaced apart in the Z direction with the optical axis AX as the center are the first prism member. It passes through the peripheral cone 6d of 6a and the peripheral cone 6f of the second prism member 6b.

  Here, in the state where the concave refractive surface of the first prism member 6a and the convex refractive surface of the second prism member 6b are in contact with each other, the prism pair 6 is parallel to the central light beam 31a and the two peripheral light beams 31b. It functions as a flat plate and has no effect on the Z-direction tripolar secondary light source formed. However, if the concave refracting surface of the first prism member 6a and the convex refracting surface of the second prism member 6b are separated, the prism pair 6 does not affect the central light beam 31a, but the two peripheral light beams 31b are affected. On the other hand, the prism pair 6 functions as a so-called beam expander.

  FIG. 4 is a diagram for explaining the action of the prism pair with respect to the Z-direction tripolar secondary light source. As shown in FIG. 4, the two circular peripheral surface light sources 32b constituting the Z-direction tripolar secondary light source expand the distance between the prism pair 6 from zero to a predetermined value, thereby increasing the optical axis AX. And moves outward along the radial direction of the circle, and the shape changes from a circular shape to an elliptical shape. That is, a line segment connecting the center point of the circular peripheral surface light source 32b before the change and the center point of the elliptical peripheral surface light source 33b after the change passes through the optical axis AX, and the movement distance of the center point is the prism pair 6. Depends on the interval.

  Further, an angle at which the circular peripheral surface light source 32b before the change is viewed from the optical axis AX (an angle formed by a pair of tangent lines from the optical axis AX to the peripheral surface light source 32b) and an elliptical peripheral surface light source 33b after the change are displayed. The angle seen from the optical axis AX is equal. Then, the diameter of the circular peripheral surface light source 32b before the change, that is, the difference between the radius of the circle circumscribing the two peripheral surface light sources 32b as the optical axis AX and the radius of the inscribed circle, and the changed ellipse as the optical axis AX The difference between the radius of the circle circumscribing the shape peripheral surface light source 33b and the radius of the inscribed circle is equal. Thus, the circular peripheral surface light source 32b changes in the circumferential direction depending on the interval between the prism pairs 6, but does not change in the radial direction. On the other hand, the circular center plane light source 32a constituting the Z direction tripolar secondary light source is not affected even when the interval between the prism pair 6 is increased from zero to a predetermined value.

  Therefore, when the interval between the prism pair 6 is increased from zero to a predetermined value, the positions and sizes of the two circular peripheral surface light sources 32b constituting the Z-direction tripolar secondary light source are set in the Z-direction tripolar. It changes independently from the circular center surface light source 32a which constitutes a secondary light source. In other words, the prism pair 6 has the position and size of the light intensity distribution (two peripheral surface light sources 32b) formed in the pupil plane or in the vicinity thereof and positioned in a plurality of peripheral regions spaced from the optical axis AX. A region changing means for changing independently of the light intensity distribution (center surface light source 32a) located in the central region including the optical axis AX and formed in or near the pupil surface is configured.

  FIG. 5 is a diagram for explaining the operation of the zoom lens with respect to the Z direction tripolar secondary light source. As shown in FIG. 5, when the focal length of the zoom lens 7 changes, the two circular peripheral surface light sources 32b spaced apart in the Z direction with the optical axis AX as the center have the optical axis AX while maintaining the circular shape. It moves along the radial direction of the circle centered on. A line segment connecting the center point of the peripheral surface light source 32b before the change and the center point of the peripheral surface light source 34b after the change passes through the optical axis AX, and the moving distance and the moving direction of the center point are the focus of the zoom lens 7. Depends on distance change.

  The angle at which the peripheral surface light source 32b before the change is viewed from the optical axis AX is equal to the angle at which the peripheral surface light source 34b after the change is viewed from the optical axis AX. On the other hand, when the focal length of the zoom lens 7 changes, the center point of the circular center plane light source 32a centering on the optical axis AX does not move, but its size changes. Specifically, the ratio of the diameter of the central surface light source 32a before the change to the diameter of the central surface light source 34a after the change is the difference between the diameter of the peripheral surface light source 32b before the change and the diameter of the peripheral surface light source 34b after the change. It is the same as the ratio. Thus, by changing the focal length of the zoom lens 7, the overall shape of the tripolar secondary light source can be changed in a similar manner.

  Instead of the diffractive optical element 3 for Z direction tripolar illumination, a diffractive optical element for X direction tripolar illumination can be set in the illumination optical path to perform X direction tripolar illumination. The diffractive optical element for X-direction tripolar illumination, when a parallel light beam enters, is spaced in the far field, for example, a circular light intensity distribution centered on the optical axis AX and the optical axis AX in the X direction. And has a function of forming three circular light intensity distributions composed of two circular light intensity distributions separated from each other. Accordingly, the light beam that has passed through the diffractive optical element for X-direction triode illumination has a circular light intensity distribution (center surface light source) 30a centered on the optical axis AX and the optical axis, as shown in FIG. An X-direction tripolar secondary light source is formed, which includes two circular light intensity distributions (peripheral surface light sources) 30c spaced from each other in the X direction with AX as the center.

  Then, as shown in FIG. 6, when the interval between the prism pair 6 is increased from zero to a predetermined value, a secondary light source having a tripolar shape in the X direction is formed as in the case of tripolar illumination in the Z direction in FIG. The position and size of the two circular peripheral surface light sources 32c to be changed independently of the circular central surface light source 32a constituting the X direction tripolar secondary light source. That is, the circular peripheral surface light source 32c is moved in the radial direction depending on the distance between the prism pairs 6, and the size thereof is changed only in the circumferential direction. become. On the other hand, the center position and size of the circular center surface light source 32a do not change even if the interval between the prism pairs 6 changes.

  Further, as shown in FIG. 7, when the focal length of the zoom lens 7 is changed, a circular central surface light source 32a and two circular peripheral surface light sources are provided, as in the case of Z-direction tripolar illumination in FIG. The overall shape of the X direction tripolar secondary light source consisting of 32c changes in a similar manner. In other words, the circular peripheral surface light source 32c depends on the change in the focal length of the zoom lens 7, the center position thereof moves in the radial direction, and the size thereof changes in a similar manner. It becomes the light source 34c. On the other hand, the circular center plane light source 32a depends on the change in the focal length of the zoom lens 7 and changes in size in a similar manner to become a circular center plane light source 34a, but the center position changes. do not do.

  Further, in place of the diffractive optical element 3 for Z-direction tripolar illumination, pentode illumination can be performed by setting a diffractive optical element for pentapole illumination in the illumination optical path. The diffractive optical element for pentode illumination has, for example, a circular light intensity distribution centered on the optical axis AX and the X direction centered on the optical axis AX in the far field when a parallel light beam enters. It has a function of forming five circular light intensity distributions consisting of four circular light intensity distributions arranged at the positions of the respective vertices of a square (or a rectangle) having sides along the Z direction. Therefore, as shown in FIG. 8A, the light beam that has passed through the diffractive optical element for pentode illumination has a circular light intensity distribution (center surface light source) 30a centered on the optical axis AX and the optical axis AX. A five-pole two-polar light distribution (peripheral surface light source) 30d arranged at the position of each vertex of a square having a side along the X direction and a side along the Z direction. The next light source is formed.

  Then, as shown in FIG. 9, when the interval between the prism pair 6 is increased from zero to a predetermined value, as in the case of the Z direction tripolar illumination in FIG. 4 and the X direction tripolar illumination in FIG. The positions and sizes of the four circular peripheral surface light sources 32d constituting the secondary light source of the shape change independently of the circular central surface light source 32a constituting the secondary light source having the pentapole shape. In other words, the circular peripheral surface light source 32d moves in the radial direction depending on the interval between the prism pairs 6, and its size changes only in the circumferential direction, so that the elliptical peripheral surface light source 33d changes. become. On the other hand, the center position and size of the circular center surface light source 32a do not change even if the interval between the prism pairs 6 changes.

  Further, as shown in FIG. 10, when the focal length of the zoom lens 7 is changed, a circular center plane light source 32a is provided as in the case of the Z direction tripolar illumination in FIG. 5 and the X direction tripolar illumination in FIG. The four-pole secondary light source comprising the four circular peripheral surface light sources 32d changes in a similar manner. That is, the circular peripheral surface light source 32d has its center position moved in the radial direction depending on the change in the focal length of the zoom lens 7, and the size thereof is changed in a similar manner. It becomes the light source 34d. On the other hand, the circular center plane light source 32a depends on the change in the focal length of the zoom lens 7 and changes in size in a similar manner to become a circular center plane light source 34a, but the center position changes. do not do.

  Further, instead of the diffractive optical element 3 for Z-direction tripolar illumination, nine-pole illumination can be performed by setting a diffractive optical element for nine-pole illumination in the illumination optical path. The diffractive optical element for nine-pole illumination, when a parallel light beam is incident, has, for example, a circular light intensity distribution centered on the optical axis AX and a X-direction centered on the optical axis AX. Four circular light intensity distributions arranged at the positions of the vertices of a first square (or first rectangle) having a side and a side along the Z direction, and a side along the X direction about the optical axis AX And four circular light intensity distributions arranged at the positions of the vertices of the second square (or second rectangle) having sides along the Z direction and surrounding the first square (or first rectangle); 5 has a function of forming a light intensity distribution of five circular shapes.

  Accordingly, the light beam that has passed through the diffractive optical element for nine-pole illumination has a circular light intensity distribution (center surface light source) 30a centered on the optical axis AX and the optical axis AX as shown in FIG. Four circular light intensity distributions (inner peripheral surface light sources) 30e arranged at the positions of the vertices of the first square having sides along the X direction and sides along the Z direction, and an optical axis AX Four circular light intensity distributions (outer peripheral surfaces) arranged at positions of respective vertices of the second square having sides along the X direction and sides along the Z direction and surrounding the first square. A nine-pole secondary light source consisting of 30f is formed.

  In this case, although not shown, when the interval between the prism pair 6 is increased from zero to a predetermined value, the four circles constituting the nine-pole secondary light source are formed as in the case of the five-pole illumination in FIG. The positions and sizes of the shape inner peripheral surface light source and the four circular outer peripheral surface light sources change independently of the circular central surface light source constituting the nine-pole secondary light source. That is, the circular inner peripheral surface light source and the outer peripheral surface light source move in the radial direction depending on the distance between the prism pairs 6, and the size thereof changes only in the circumferential direction. The inner peripheral surface light source and the outer peripheral light source. On the other hand, the center position and size of the circular center surface light source do not change even if the interval between the prism pair 6 changes.

  When the focal length of the zoom lens 7 is changed, a circular central surface light source, four circular inner peripheral surface light sources, and four circular outer peripheral surfaces are provided, as in the case of the pentapolar illumination in FIG. The overall shape of the nine-pole secondary light source composed of the light source changes similarly. That is, the circular inner peripheral surface light source and the outer peripheral surface light source depend on the change in the focal length of the zoom lens 7, the center position thereof moves in the radial direction, and the size thereof changes similarly. It becomes a circular inner peripheral surface light source and an outer peripheral surface light source. On the other hand, depending on the change in the focal length of the zoom lens 7, the circular center plane light source changes in size in a similar manner to become a circular center plane light source, but the center position does not change.

  In the above description, in the case of nine-pole illumination, a single-stage prism pair 6 having a refracting surface having one peripheral cone (6d, 6f) is used as shown in FIG. However, in the case of nine-pole illumination, it is also possible to use a two-stage prism pair 60 whose refractive surface has two peripheral cones as shown in FIG. Referring to FIG. 11, the two-stage prism pair 60 includes, in order from the light source side, a first prism member 60 a having a flat surface facing the light source side and a refractive surface having a concave cross section facing the mask side, and a flat surface facing the mask side. In addition, the second prism member 60b having a refracting surface with a convex cross section facing the light source side. The concave refracting surface of the first prism member 60a and the convex refracting surface of the second prism member 60b are complementarily formed so as to be in contact with each other.

  More specifically, the refracting surface of the concave section of the first prism member 60a has a planar central portion 60c orthogonal to the optical axis AX and an inner side corresponding to the side surface of the first cone centered on the optical axis AX. The peripheral cone portion 60d has an outer peripheral cone portion 60e corresponding to the side surface of the second cone having the apex angle smaller than that of the first cone and having the optical axis AX as the center. Similarly, the refractive surface of the convex cross section of the second prism member 60b has a planar central portion 60f orthogonal to the optical axis AX and an inner peripheral cone corresponding to the side surface of the first cone centered on the optical axis AX. Part 60g and an outer peripheral cone part 60h corresponding to the side surface of the second cone having the apex angle smaller than that of the first cone with the optical axis AX as the center. In addition, at least one of the first prism member 60a and the second prism member 60b is configured to be movable along the optical axis AX, and the concave surface of the first prism member 60a has a refractive surface and the second prism member 60b. The interval between the convex cross section and the refractive surface is variable.

  In the two-stage prism pair 60, as shown in FIG. 11, a central light beam 31a that forms a circular center surface light source 30a centering on the optical axis AX among the nine-pole secondary light sources is a first prism member. It passes through the central portion 60c of 60a and the central portion 60f of the second prism member 60b. Of the nine-pole secondary light sources, the four inner peripheral light beams 31e forming the four inner peripheral surface light sources 30e arranged at the positions of the vertices of the first square centered on the optical axis AX are It passes through the inner peripheral conical portion 60d of the first prism member 60a and the peripheral conical portion 60g of the second prism member 60b. Of the nine-pole secondary light sources, the four outer peripheral light beams 31f forming the four outer peripheral surface light sources 30f arranged at the positions of the vertices of the second square centered on the optical axis AX are It passes through the outer peripheral cone portion 60e of the first prism member 60a and the peripheral cone portion 60h of the second prism member 60b.

  Here, when the concave refractive surface of the first prism member 60a and the convex refractive surface of the second prism member 60b are in contact with each other, the central light beam 31a, the four inner peripheral light beams 31e, and the four outer peripheral light beams 31f. On the other hand, the two-stage prism pair 60 functions as a plane-parallel plate and has no influence on the formed nine-pole secondary light source. However, if the concave refracting surface of the first prism member 60a and the convex refracting surface of the second prism member 60b are separated from each other, the two-stage prism pair 60 does not affect the central light beam 31a. The two-stage prism pair 60 functions as a so-called beam expander for the peripheral light beam 31e and the four outer peripheral light beams 31f.

  FIG. 12 is a diagram for explaining the action of the two-stage prism pair for the nine-pole secondary light source. However, in FIG. 12, only the center surface light source 32a, one inner peripheral surface light source 32e, and one outer peripheral surface light source 32f are shown among the nine-pole secondary light sources for the sake of clarity. . As shown in FIG. 12, the inner peripheral surface light source 32e and the outer peripheral surface light source 32f expand the distance between the two-stage prism pair 60 from zero to a predetermined value, thereby increasing the diameter of the circle centered on the optical axis AX. As it moves outward along the direction, its shape changes from a circular shape to an elliptical shape. That is, the line segment connecting the center points of the circular inner peripheral surface light source 32e and the outer peripheral surface light source 32f before the change and the center points of the elliptical inner peripheral surface light source 33e and the outer peripheral surface light source 33f after the change is light. The movement distance of the center point through the axis AX depends on the distance between the two-stage prism pair 60.

  Here, in the case of the two-stage prism pair 60, the moving distance from the circular outer peripheral surface light source 32f before the change to the elliptical outer peripheral light source 33f after the change is the circular shape before the change. The moving distance from the inner peripheral surface light source 32e to the elliptical inner peripheral surface light source 33e after the change becomes larger, and the difference in the moving distance changes depending on the distance between the two-stage prism pair 60. Further, the angle at which the circular inner peripheral surface light source 32e before the change is viewed from the optical axis AX (the angle formed by a pair of tangent lines from the optical axis AX to the inner peripheral surface light source 32e), and the elliptical inner peripheral surface after the change The angle at which the light source 33e is viewed from the optical axis AX is equal.

  Similarly, an angle at which the circular outer peripheral surface light source 32f before the change is viewed from the optical axis AX (an angle formed by a pair of tangents from the optical axis AX to the outer peripheral light source 32f) and the outer periphery of the elliptical shape after the change The angle at which the surface light source 33f is viewed from the optical axis AX is equal. When the circular inner peripheral surface light source 32e before the change and the circular outer peripheral light source 32f before the change have the same size, the circular inner peripheral surface light source 32e before the change has the optical axis AX. Is larger than the angle at which the circular outer peripheral surface light source 32f before the change is viewed from the optical axis AX.

  Then, the diameter of the circular inner peripheral surface light source 32e before the change, that is, the difference between the radius of the circle circumscribing the four inner peripheral surface light sources 32e and the radius of the inscribed circle as the optical axis AX, and the optical axis AX after the change The difference between the radius of the circle circumscribing the inner peripheral surface light source 33e and the radius of the inscribed circle is equal. Similarly, the diameter of the circular outer peripheral surface light source 32f before the change, that is, the difference between the radius of the circle circumscribing the four outer peripheral surface light sources 32f and the radius of the inscribed circle as the optical axis AX, and the optical axis AX are changed. The difference between the radius of the circle circumscribing the outer elliptical outer peripheral surface light source 33f and the radius of the inscribed circle is equal. On the other hand, the circular center plane light source 32a constituting the nine-pole secondary light source is not affected even if the interval of the two-stage prism pair 60 is increased from zero to a predetermined value.

  As described above, in the first embodiment, a plurality of prisms 6 (or two-stage prism pair 60) that are formed in or near the pupil plane and spaced apart from the optical axis AX by the action of the prism pair 6 (or the two-stage prism pair 60) as the region changing means. The position and size of the light intensity distribution (peripheral surface light source) located in the peripheral region of the light source can be changed independently of the light intensity distribution (center surface light source) located in the central region including the optical axis AX. As a result, in the first embodiment, for example, the positions and sizes of a plurality of peripheral surface light sources that are changed independently of the central surface light source are rich in diversity (that is, the light intensity formed on or near the pupil surface). 3-pole illumination, 5-pole illumination, and 9-pole illumination, which are diverse in terms of distribution, can be realized.

  In the first embodiment described above, a secondary light source including a circular central surface light source centered on the optical axis AX and a plurality of circular peripheral surface light sources arranged symmetrically with respect to the optical axis AX is formed. ing. However, the shape and position of each surface light source are not limited to this, and in general, the light intensity distribution located in the central area including the optical axis AX and the light located in a plurality of peripheral areas spaced from the optical axis AX. A secondary light source (illumination pupil distribution) having an intensity distribution can be formed.

  Further, in the first embodiment described above, the central light source including the optical axis AX and the peripheral light sources spaced from the optical axis AX form a secondary light source having substantially the same size. However, the present invention is not limited to this. By setting a diffractive optical element having desired characteristics in the illumination optical path, the center surface light source can be made substantially larger than each peripheral surface light source, or more than each peripheral surface light source. A modification in which the center plane light source is substantially reduced is also possible. In this case, it is preferable that one or a plurality of prism pairs having different areas in the central portion are provided to be exchangeable.

  Specifically, when the central surface light source is set to be substantially smaller than the peripheral surface light sources, a prism pair having a relatively small central area as shown in FIG. 12A can be used. When the center surface light source is set to be substantially larger than each peripheral surface light source, a prism pair having a relatively large area at the center as shown in FIG. 12B can be used. FIG. 12 shows only an example of a single-stage prism pair. However, if necessary, one or a plurality of two-stage prism pairs having different central areas can be exchanged. preferable.

  FIG. 14 is a drawing schematically showing a configuration of an exposure apparatus including an illumination optical apparatus according to the second embodiment of the present invention. FIG. 15 is a diagram schematically showing a main configuration of the second embodiment. In FIG. 14 and FIG. 15, the illumination optical device is set in a Z-direction tripolar illumination state. The second embodiment has a configuration similar to that of the first embodiment. However, in the second embodiment, the quarter-wave plate 12 and the half-wave plate 13 are attached to the light source side of the prism pair 6, and the half-wave plate 14 and the deflection prism assembly are attached to the mask side of the prism pair 6. The point to which the solid 15 is attached is different from the first embodiment. Hereinafter, the second embodiment will be described by paying attention to differences from the first embodiment.

  14 and 15, in the second embodiment, in the optical path between the front lens group 4a of the afocal lens 4 and the prism pair 6, the crystal optical axis is centered on the optical axis AX in order from the light source side. A quarter-wave plate 12 that is configured to be rotatable and a half-wave plate 13 that is configured so that the crystal optical axis is rotatable about the optical axis AX are disposed. Here, the quarter wave plate 12 has a function of converting incident elliptically polarized light into linearly polarized light. The half-wave plate 13 has a function of converting incident linearly polarized light into linearly polarized light having a polarization plane in a predetermined direction.

  When a KrF excimer laser light source or an ArF excimer laser light source is used as the light source 1, substantially linearly polarized light is supplied from the light source 1. Further, in the optical path between the light source 1 and the diffractive optical element 3, it is usual that a plurality of right-angle prisms as back reflectors are arranged. In general, when linearly polarized light is incident on a right-angle prism as a back reflector, if the polarization plane of the incident linearly polarized light does not coincide with the P-polarization plane or the S-polarization plane, the linearly polarized light becomes elliptical due to total reflection at the right-angle prism. Changes to polarized light.

  In the second embodiment, for example, even when elliptically polarized light is incident on the diffractive optical element 3 due to a right-angle prism, the crystal optical axis of the quarter-wave plate 12 is set according to the characteristics of the incident elliptically polarized light. As a result, the linearly polarized light enters the subsequent half-wave plate 13. The linearly polarized light incident on the half-wave plate 13 is converted into linearly polarized light having a polarization plane in an arbitrary direction according to the direction of the crystal optical axis. Thus, linearly polarized light having a polarization plane in an arbitrary direction is guided to the prism pair 6 by the cooperative action of the quarter-wave plate 12 and the half-wave plate 13. Even if the quarter-wave plate 12 is arranged on the mask side of the half-wave plate 13, an optically equivalent effect can be obtained.

  In the second embodiment, between the prism pair 6 and the rear lens group 4b of the afocal lens 4, two peripheral light beams 31b forming two peripheral surface light sources 30b spaced from the optical axis AX are used. In the optical path, an annular half-wave plate 14 in which the crystal optical axis is rotatable about the optical axis AX is disposed. Further, between the prism pair 6 and the rear lens group 4b of the afocal lens 4, there is a wedge-shaped quartz prism 15a in the optical path of the central light beam 31a that forms the central surface light source 30a including the optical axis AX. A declination prism assembly 15 integrally formed by the quartz prism 15a and a wedge-shaped quartz prism 15b having a complementary shape is disposed.

  The declination prism assembly 15 is configured to be rotatable about the optical axis AX. Further, in the declination prism assembly 15, the apex direction of the quartz prism 15a and the apex direction of the quartz prism 15b are set in opposite directions, and the declination action by the quartz prism 15a is compensated (corrected) by the quartz prism 15b. It is configured. In the declination prism assembly 15, the crystal prism 15 a is set so that the direction of the crystal optical axis of the crystal prism 15 a forms an angle of 45 degrees with respect to the incident plane of linearly polarized light. Light is converted into substantially unpolarized light. On the other hand, if the crystal optical axis direction of the crystal prism 15a is set at an angle of 0 degree or 90 degrees with respect to the polarization plane of the incident linearly polarized light, the polarization plane of the incident linearly polarized light is not changed and remains unchanged. It passes through the prism assembly 15.

  Thus, the half-wave plate 14 constitutes a phase member for changing the polarization plane of the linearly polarized light beam toward the two peripheral surface light sources 30b spaced from the optical axis AX as necessary. Specifically, by setting the crystal optical axis of the half-wave plate 14 to a required angular position, the polarization state of the light reaching the two peripheral surface light sources 30b is changed into linearly polarized light having a polarization plane in an arbitrary direction. Can be set to state.

  Further, the declination prism assembly 15 constitutes a depolarizing element for depolarizing linearly polarized light fluxes toward the central surface light source 30a including the optical axis AX as necessary. Specifically, by setting the crystal optical axis of the crystal prism 15a in the declination prism assembly 15 to a required angular position, the polarization state of the light reaching the center plane light source 30a is changed into a linear polarization state and a non-polarization state. Can be switched between. Alternatively, the polarization prism assembly 15 is configured to be detachable with respect to the optical path, and the polarization prism assembly 15 is set in the optical path to realize a non-polarized state, or the polarization prism assembly 15 is configured to be in the optical path. By retracting from the position, it is possible to achieve a linearly polarized state while avoiding light loss. Hereinafter, a setting example of the polarization state of the peripheral surface light source and the central surface light source in the three-pole illumination, the five-pole illumination, and the nine-pole illumination according to the second embodiment will be specifically described.

  FIG. 16 is a diagram for explaining a setting example of the polarization state of the peripheral surface light source and the central surface light source in the tripolar illumination of the second embodiment. In the case of the Z-direction tripolar illumination or the X-direction tripolar illumination, as shown in FIG. 16, an interval is provided around the optical axis AX along the pitch direction of the line and space pattern 51 formed on the mask. A straight line that forms two peripheral surface light sources 41b and has a polarization plane (indicated by a double-pointed arrow in the figure) in a direction orthogonal to the pitch direction of the pattern 51, for example, for the polarization state of the light beam passing through the two peripheral surface light sources 41b Set to polarization state. Further, the polarization state of the light beam passing through the center plane light source 41a with the optical axis AX as the center is set to, for example, a non-polarization state.

  In this case, dipole illumination suitable for the line and space pattern 51 (mask illumination by light beams from the two peripheral surface light sources 41b) and small σ illumination suitable for the isolated pattern 52 (from the central surface light source 41a). With the tripolar illumination that is combined with the illumination of the mask by the luminous flux, it is possible to realize faithful pattern transfer while improving the imaging performance of the projection optical system. In tripolar illumination, the polarization state of the light beam passing through the center plane light source 41a can be set to a linear polarization state having a polarization plane in a desired direction. In addition, the polarization state of the light beam passing through the two peripheral surface light sources 41b can be set to a linear polarization state having a polarization plane in a desired direction.

  FIG. 17 is a diagram for explaining a setting example of the polarization state of the peripheral surface light source and the central surface light source in the pentapolar illumination of the second embodiment. In the case of pentapolar illumination, as shown in FIG. 17, there are four peripheral surfaces at each vertex of a square (or rectangle) having sides along the pitch direction of the line and space pattern 51 formed on the mask. The light source 41d is formed, and the polarization state of the light beam passing through the four peripheral surface light sources 41d is set to a linear polarization state having a polarization plane (indicated by a double arrow in the figure) in a direction orthogonal to the pitch direction of the pattern 51, for example. To do. Further, the polarization state of the light beam passing through the center plane light source 41a with the optical axis AX as the center is set to, for example, a non-polarization state.

  In this case, quadrupole illumination suitable for the line and space pattern 51 (mask illumination by light beams from the four peripheral surface light sources 41d) and small σ illumination suitable for the isolated pattern 52 (from the central surface light source 41a). By using the five-pole illumination in combination with the illumination of the mask by the luminous flux, it is possible to realize faithful pattern transfer while improving the imaging performance of the projection optical system. Note that, in pentapolar illumination, the polarization state of the light beam passing through the center plane light source 41a can be set to a linear polarization state having a polarization plane in a desired direction. Also, the polarization state of the light beam passing through the four peripheral surface light sources 41d can be set to a linear polarization state having a polarization plane in a desired direction. In particular, the polarization state of the light beam passing through the four peripheral surface light sources 41d can be set to a linear polarization state having a polarization surface in a direction that forms an angle of 45 degrees with the interval direction of the peripheral surface light sources 41d, for example.

  Further, the polarization state of the light beam passing through each peripheral surface light source 41d can be set to a linear polarization state having a polarization plane in a desired direction. Typically, as shown in FIG. 18, among the four peripheral surface light sources, the polarization state of the light beam passing through one pair of peripheral surface light sources 41d1 and 41d3 facing each other across the optical axis AX is expressed as a peripheral surface light source. A light beam passing through the other pair of peripheral surface light sources 41d2 and 41d4 facing each other across the optical axis AX is set in a linear polarization state having a polarization plane in the same direction that forms an angle of 45 degrees with the interval direction between 41d1 and 41d3. Can be set to a linear polarization state having a polarization plane in a direction orthogonal to the polarization plane direction of the linear polarization passing through the peripheral surface light sources 41d1 and 41d3. However, in order to realize the polarization state shown in FIG. 18, in place of the ring-shaped half-wave plate 14 shown in FIG. 15, the first light path of the light beam directed to one pair of peripheral surface light sources 41d1 and 41d3 is used. And a second half-wave plate must be provided in the optical path of the light beam toward the other pair of peripheral surface light sources 41d2 and 41d4.

  FIG. 19 is a diagram illustrating an example of setting the polarization states of the peripheral surface light source and the central surface light source in the nine-pole illumination according to the second embodiment. In the case of nine-pole illumination, as shown in FIG. 19, there are four inner peripheries at the positions of each vertex of a square (or rectangle) having sides along the pitch direction of the line and space pattern 51a formed on the mask. A linear polarization state in which the surface light source 41e is formed and the polarization state of the light beam passing through the four inner peripheral surface light sources 41e has a polarization plane (indicated by a double-headed arrow in the figure) in a direction orthogonal to the pitch direction of the pattern 51a, for example. Set to. The polarization state of the light beam passing through the four outer peripheral surface light sources 41f is changed to a polarization plane (indicated by a double arrow in the figure) in a direction perpendicular to the polarization plane direction of the linearly polarized light passing through the four inner peripheral surface light sources 41e. The linear polarization state is set.

  Further, the polarization state of the light beam passing through the center plane light source 41a with the optical axis AX as the center is set to, for example, a non-polarization state. In this case, quadrupole illumination suitable for the line and space pattern 51a (illumination of the mask by the light flux from the four inner peripheral surface light sources 41e) is finer than the pattern 51a and orthogonal to the pitch direction of the pattern 51a. Quadrupole illumination suitable for the line-and-space pattern 51b having the pitch direction (mask illumination by light beams from the four outer peripheral surface light sources 41f) and small σ illumination suitable for the isolated pattern 52 (center surface light source 41a) The nine-pole illumination that is combined with the illumination of the mask by the luminous flux of the light beam can realize faithful pattern transfer while improving the imaging performance of the projection optical system.

  In the nine-pole illumination, the polarization state of the light beam passing through the center plane light source 41a can be set to a linear polarization state having a polarization plane in a desired direction. Further, the polarization state of the light beam passing through the four inner peripheral surface light sources 41e and the polarization state of the light beam passing through the four outer peripheral surface light sources 41f are set to linear polarization states having polarization surfaces in desired directions, respectively. You can also. In particular, the polarization state of the light beam passing through the four inner peripheral surface light sources 41e and the polarization state of the light beam passing through the four outer peripheral surface light sources 41f are polarized in a direction that forms an angle of 45 degrees with the interval direction of the peripheral light sources, for example. It can also be set to a linear polarization state with a plane.

  Typically, as shown in FIG. 20, among the four inner peripheral surface light sources, the polarization state of the light beam passing through one pair of inner peripheral surface light sources 41e1 and 41e3 facing each other across the optical axis AX is changed to the inner side. The other pair of inner peripheral surface light sources 41e2 and 41e4 are set in a linear polarization state having a polarization surface in the same direction that forms an angle of 45 degrees with the interval direction between the peripheral surface light sources 41e1 and 41e3 and are opposed to each other with the optical axis AX interposed therebetween. Can be set to a linear polarization state having a polarization plane in a direction orthogonal to the polarization plane direction of the linear polarization passing through the inner peripheral surface light sources 41e1 and 41e3.

  Similarly, of the four outer peripheral surface light sources, the polarization state of the light beam passing through one pair of outer peripheral surface light sources 41f1 and 41f3 facing each other with the optical axis AX interposed therebetween is expressed as the distance between the outer peripheral surface light sources 41f1 and 41f3. The polarization state of the light beam passing through the other pair of outer peripheral surface light sources 41f2 and 41f4 facing each other across the optical axis AX is set to a linear polarization state having a polarization plane in the same direction that forms an angle of 45 degrees with the direction. A linear polarization state having a polarization plane in a direction orthogonal to the polarization plane direction of the linear polarization passing through the outer peripheral surface light sources 41f1 and 41f3 can also be set.

  However, in order to realize the polarization state shown in FIG. 19, as shown in FIG. 21, a two-stage prism pair 60 is arranged instead of the prism pair 6 shown in FIG. 15 (or the prism pair 6 is used as it is). , Instead of the annular half-wave plate 14 shown in FIG. 15, the first annular half-wave that can rotate about the optical axis AX in the optical path of the light beam 31 e toward the inner peripheral surface light source 41 e. In addition to providing the plate 14a, it is necessary to provide a second annular half-wave plate 14b that can be rotated about the optical axis AX in the optical path of the light beam 31f toward the outer peripheral surface light source 41f.

  Alternatively, as shown in FIG. 22, in place of the first annular half-wave plate 14a of FIG. 21, in the optical path of the light beam 31a toward the center surface light source 41a and the light beam 31e toward the inner peripheral surface light source 41e. A first circular half-wave plate 14c that can be rotated about the optical axis AX is provided, and instead of the second annular half-wave plate 14b in FIG. A configuration in which a second circular half-wave plate 14d that can rotate around the optical axis AX is provided in the optical path of the light beam 31a, the light beam 31e toward the inner peripheral surface light source 41e, and the light beam 31f toward the outer peripheral surface light source 41f. Is also possible.

  In the configuration of FIG. 22, both the polarization state of the light beam passing through the inner peripheral surface light source 41e and the polarization state of the light beam passing through the outer peripheral surface light source 41f can be set to the horizontal polarization state or the vertical polarization state. Alternatively, the polarization state of the light beam passing through the inner peripheral surface light source 41e can be set to the lateral polarization state, and the polarization state of the light beam passing through the outer peripheral surface light source 41f can be set to the vertical polarization state. Alternatively, the polarization state of the light beam passing through the inner peripheral surface light source 41e can be set to a longitudinal polarization state, and the polarization state of the light beam passing through the outer peripheral surface light source 41f can be set to a lateral polarization state.

  On the other hand, in order to realize the polarization state shown in FIG. 20, a two-stage prism pair 60 is arranged in place of the prism pair 6 shown in FIG. 15 (or the prism pair 6 is used as it is), and the annular shape shown in FIG. In place of the half-wave plate 14, a first half-wave plate is provided in the optical path of the light beam directed to one pair of inner peripheral surface light sources 41 e 1 and 41 e 3, and the other pair of inner peripheral surface light sources 41 e 2 and 41 e 2 A second half-wave plate is provided in the optical path of the light beam toward 41e4, a third half-wave plate is provided in the optical path of the light beam toward one pair of outer peripheral surface light sources 41f1 and 41f3, and the other It is necessary to provide a fourth half-wave plate in the optical path of the light beam toward the pair of outer peripheral surface light sources 41f2 and 41f4.

  As described above, in the second embodiment, the half-wave plate 14 and the declination prism assembly 15 are center plane light sources centered on the optical axis AX (generally, the center including the optical axis at or near the pupil plane). The light beam passing through the first region as a region is set to a non-polarized state, and a peripheral surface light source spaced from the optical axis AX (generally, one spaced from the optical axis at or near the pupil plane or Polarization setting means for setting a light beam passing through a plurality of second regions (peripheral regions) to a linear polarization state (generally a polarization state) is configured.

  Further, according to another aspect, the half-wave plate 14 and the declination prism assembly 15 are separated from the optical axis at a peripheral surface light source (generally at or near the pupil plane) spaced from the optical axis AX. The polarization state of the light beam passing through one or more second regions as a peripheral region is determined as a center plane light source centered on the optical axis AX (generally as a central region including the optical axis at or near the pupil plane). Polarization state changing means for changing the polarization state of the light beam passing through the first region) independently of each other is configured. The polarization state changing means (14, 15) changes, for example, the state of the light beam passing through the central surface light source (first region) centered on the optical axis AX between the non-polarized state and the linearly polarized state.

  Further, the polarization state changing means (14, 15) has two linear lines having polarization planes in different directions, for example, with respect to the polarization state of the light beam passing through the peripheral surface light source (second region) spaced from the optical axis AX. Change between polarization states. As a result, in the second embodiment, in addition to the effect of the first embodiment, it is possible to realize a three-pole illumination, a five-pole illumination, and a nine-pole illumination that are rich in diversity with respect to the position and size of the peripheral surface light source. The three-pole illumination, the five-pole illumination, and the nine-pole illumination that are rich in the polarization states (including the non-polarized state) of the peripheral surface light source and the central surface light source can be realized.

  In the second embodiment described above, a diffractive optical element for annular illumination is set in the illumination optical path instead of the diffractive optical element 3 for Z-direction tripolar illumination, and a refractive surface is used instead of the prism pair 6. By using a prism pair having only one conical portion without having a flat central portion (hereinafter referred to as “conical prism pair”), annular illumination can be performed. The diffractive optical element for annular illumination has a function of forming, for example, a circular light intensity distribution around the optical axis AX in the far field when a parallel light beam is incident.

  Accordingly, the light beam that has passed through the diffractive optical element for annular illumination forms a circular light intensity distribution around the optical axis AX on the pupil plane of the afocal lens 4. And according to the space | interval of a conical prism pair, the annular illumination field centering on the optical axis AX is formed in the entrance plane of the micro lens array 8. FIG. As a result, on the rear focal plane of the microlens array 8 (the pupil plane of the illumination optical device or its vicinity), as shown in FIG. 23A, a substantial annular zone with the optical axis AX as the center. A light source 35 is formed.

  Usually, a light beam passing through a ring-shaped surface light source has a constant polarization state (including a non-polarization state) over the whole. On the other hand, the ring-shaped surface light source 35 shown in FIG. 23A has a plurality (eight in FIG. 23) of regions 35a to 35h along the circumferential direction of the circle centered on the optical axis AX. The polarization state of the light beam passing through each of the regions 35a to 35h is set to a linear polarization state having a polarization plane (indicated by a double-headed arrow in the figure) along a direction substantially in contact with the circle at the center of each of the regions 35a to 35h. Yes.

  In order to realize the polarization state shown in FIG. 23A, for example, the phase member assembly shown in FIG. 23B is used instead of the annular half-wave plate 14 and the declination prism assembly 15 shown in FIG. It is necessary to set the solid 16 in the optical path. Here, the phase member 16 has eight phase members 16a to 16h corresponding to the eight regions 35a to 35h constituting the annular surface light source 35, and each phase member 16a to 16h is incident linearly polarized light. The plane of polarization is changed as necessary. Specifically, when linearly polarized light having a plane of polarization in the horizontal direction in the drawing, that is, horizontally polarized light is incident on the phase member 16, the phase members 16a and 16e form a direction that forms an angle of 0 degrees with respect to the horizontal direction in the drawing. Are formed by a half-wave plate having a crystal optical axis.

  The phase members 16c and 16g are formed of half-wave plates having a crystal optical axis in a direction forming an angle of 45 degrees with respect to the horizontal direction in the drawing. The phase members 16b and 16f are formed of half-wave plates having crystal optical axes in a direction that forms an angle of 22.5 degrees counterclockwise with respect to the horizontal direction in the drawing. The phase members 16d and 16h are formed of half-wave plates having a crystal optical axis in a direction that makes an angle of 22.5 degrees clockwise with respect to the horizontal direction in the drawing.

  With this configuration, the light irradiated onto the mask M or the wafer W can be set to a polarization state mainly composed of S-polarized light. If the optical system (illumination optical system or projection optical system) on the wafer W side with respect to the phase member assembly 16 has polarization aberration (retardation), it is caused by this polarization aberration (retardation). The polarization direction may change. In this case, the state in which the polarization plane is changed by the phase member assembly 16 may be set in consideration of the influence of the polarization aberration of these optical systems. Further, when a reflecting member is disposed in the optical system (illumination optical system or projection optical system) on the wafer W side of the phase member assembly 16, the reflected light has a phase difference for each polarization direction in the reflecting member. Sometimes. Even in this case, the phase member assembly 16 may set the state of changing the polarization plane in consideration of the phase difference of the light beam caused by the polarization characteristics of the reflection plane. Here, the above-described matters can be applied not only to the modification shown in FIG. 23 but also to the first embodiment and the second embodiment. In the modification shown in FIG. 23, a circular center surface light source having the optical axis AX as the center may be formed in addition to the annular surface light source 35 having a polarization plane in the circumferential direction. .

  In the exposure apparatus according to the above-described embodiment, the illumination optical device illuminates the mask (reticle) (illumination process), and the projection optical system is used to expose the transfer pattern formed on the mask onto the photosensitive substrate (exposure). Step), a micro device (semiconductor element, imaging element, liquid crystal display element, thin film magnetic head, etc.) can be manufactured. Refer to the flowchart of FIG. 24 for an example of a method for obtaining a semiconductor device as a micro device by forming a predetermined circuit pattern on a wafer or the like as a photosensitive substrate using the exposure apparatus of the above-described embodiment. To explain.

  First, in step 301 of FIG. 24, a metal film is deposited on one lot of wafers. In the next step 302, a photoresist is applied on the metal film on the lot of wafers. Thereafter, in step 303, the image of the pattern on the mask is sequentially exposed and transferred to each shot area on the wafer of one lot through the projection optical system using the exposure apparatus of the above-described embodiment. Thereafter, in step 304, the photoresist on the one lot of wafers is developed, and in step 305, the resist pattern is etched on the one lot of wafers to form a pattern on the mask. Corresponding circuit patterns are formed in each shot area on each wafer. Thereafter, a device pattern such as a semiconductor element is manufactured by forming a circuit pattern of an upper layer. According to the semiconductor device manufacturing method described above, a semiconductor device having an extremely fine circuit pattern can be obtained with high throughput.

  In the exposure apparatus of the above-described embodiment, a liquid crystal display element as a micro device can be obtained by forming a predetermined pattern (circuit pattern, electrode pattern, etc.) on a plate (glass substrate). Hereinafter, an example of the technique at this time will be described with reference to the flowchart of FIG. In FIG. 25, in a pattern forming process 401, a so-called photolithography process is performed in which the exposure pattern of the above-described embodiment is used to transfer and expose a mask pattern onto a photosensitive substrate (such as a glass substrate coated with a resist). . By this photolithography process, a predetermined pattern including a large number of electrodes and the like is formed on the photosensitive substrate. Thereafter, the exposed substrate undergoes steps such as a developing step, an etching step, and a resist stripping step, whereby a predetermined pattern is formed on the substrate, and the process proceeds to the next color filter forming step 402.

  Next, in the color filter forming step 402, a large number of sets of three dots corresponding to R (Red), G (Green), and B (Blue) are arranged in a matrix or three of R, G, and B A color filter is formed by arranging a plurality of stripe filter sets in the horizontal scanning line direction. Then, after the color filter forming step 402, a cell assembly step 403 is executed. In the cell assembly step 403, a liquid crystal panel (liquid crystal cell) is assembled using the substrate having the predetermined pattern obtained in the pattern formation step 401, the color filter obtained in the color filter formation step 402, and the like.

  In the cell assembly step 403, for example, liquid crystal is injected between the substrate having the predetermined pattern obtained in the pattern formation step 401 and the color filter obtained in the color filter formation step 402, and a liquid crystal panel (liquid crystal cell) is obtained. ). Thereafter, in a module assembling step 404, components such as an electric circuit and a backlight for performing a display operation of the assembled liquid crystal panel (liquid crystal cell) are attached to complete a liquid crystal display element. According to the above-described method for manufacturing a liquid crystal display element, a liquid crystal display element having an extremely fine circuit pattern can be obtained with high throughput.

In the above-described embodiment, KrF excimer laser light (wavelength: 248 nm) or ArF excimer laser light (wavelength: 193 nm) is used as the exposure light. However, the present invention is not limited to this, and other appropriate laser light sources are used. For example, the present invention can also be applied to an F ₂ laser light source that supplies laser light having a wavelength of 157 nm. Further, in the above-described embodiment, the present invention has been described by taking the projection exposure apparatus provided with the illumination optical apparatus as an example, but the present invention is applied to a general illumination optical apparatus for illuminating an irradiated surface other than the mask. Obviously it can be done.

  In the above-described embodiment, a so-called immersion method is applied in which the optical path between the projection optical system and the photosensitive substrate is filled with a medium (typically liquid) having a refractive index larger than 1.1. You may do it. In this case, as a method of filling the liquid in the optical path between the projection optical system and the photosensitive substrate, a method of locally filling the liquid as disclosed in International Publication No. WO99 / 49504, A method of moving a stage holding a substrate to be exposed as disclosed in Japanese Patent Laid-Open No. 6-124873 in a liquid bath, or a predetermined depth on a stage as disclosed in Japanese Patent Laid-Open No. 10-303114. A technique of forming a liquid tank and holding the substrate in the liquid tank can be employed.

As the liquid, it is preferable to use a liquid that is transmissive to exposure light and has a refractive index as high as possible, and is stable with respect to a photoresist applied to the projection optical system and the substrate surface, for example, KrF excimer laser light. When ArF excimer laser light is used as exposure light, pure water or deionized water can be used as the liquid. When F ₂ laser light is used as exposure light, a fluorine-based liquid such as fluorine oil or perfluorinated polyether (PFPE) that can transmit the F ₂ laser light may be used as the liquid.

1 is a drawing schematically showing a configuration of an exposure apparatus including an illumination optical apparatus according to a first embodiment of the present invention. It is a figure which shows the Z direction tripolar secondary light source and X direction tripolar secondary light source which are formed in a pupil surface. It is a figure which shows schematically the structure and operation | movement of a prism pair arrange | positioned in the optical path between the front side lens group and back side lens group of an afocal lens. It is a figure explaining the effect | action of the prism pair with respect to a Z direction tripolar secondary light source. It is a figure explaining the effect | action of the zoom lens with respect to a Z direction tripolar secondary light source. It is a figure explaining the effect | action of the prism pair with respect to the X direction tripolar secondary light source. It is a figure explaining the effect | action of the zoom lens with respect to the X direction tripolar secondary light source. It is a figure which shows the pentapolar secondary light source and 9 pole secondary light source which are formed in a pupil surface. It is a figure explaining the effect | action of the prism pair with respect to a pentapolar secondary light source. It is a figure explaining the effect | action of the zoom lens with respect to a pentapolar secondary light source. It is a figure which shows schematically the structure and operation | movement of a two-stage prism pair for 9 pole illumination. It is a figure explaining the effect | action of the 2 step | paragraph type prism pair with respect to a 9 pole secondary light source. It is a figure which shows roughly the example of the exchangeable prism pair from which the area of a center part differs. It is a figure which shows schematically the structure of the exposure apparatus provided with the illumination optical apparatus concerning 2nd Embodiment of this invention. It is a figure which shows roughly the principal part structure of 2nd Embodiment. It is a figure explaining the example of a setting of the polarization state of the peripheral surface light source and center surface light source in the tripolar illumination of 2nd Embodiment. It is a figure explaining the example of a setting of the polarization state of the peripheral surface light source and center surface light source in the pentode illumination of 2nd Embodiment. It is a figure explaining another example of a setting of the polarization state of a peripheral surface light source and a central surface light source in pentode illumination of a 2nd embodiment. It is a figure explaining the example of a setting of the polarization state of the peripheral surface light source and center surface light source in 9 pole illumination of 2nd Embodiment. It is a figure explaining another example of the setting of the polarization state of the peripheral surface light source and center surface light source in 9 pole illumination of 2nd Embodiment. It is a figure which shows roughly an example of a principal part structure for implement | achieving the polarization state of FIG. FIG. 20 is a diagram schematically showing another example of the configuration of the main part for realizing the polarization state of FIG. 19. It is a figure explaining the example of a setting of the polarization state in the annular illumination of 2nd Embodiment. It is a flowchart of the method at the time of obtaining the semiconductor device as a microdevice. It is a flowchart of the method at the time of obtaining the liquid crystal display element as a microdevice.

Explanation of symbols

1 Light Source 3 Diffractive Optical Element 4 Afocal Lens 6 Prism Pair (Axicon System)
7 Zoom lens 8 Micro lens array 9 Condenser optical system 10 Mask blind 11 Imaging optical system 12 1/4 wavelength plate 13 1/2 wavelength plate 14 1/2 wavelength plate 15 Depolarization element 15a Quartz deflection prism 15b Quartz deflection angle Prism M Mask PL Projection optical system W Wafer

Claims (36)

In the illumination optical device that illuminates the illuminated surface,
An illumination pupil distribution having a light intensity distribution located in a central region including an optical axis and a light intensity distribution located in a plurality of peripheral regions spaced from the optical axis on or near the pupil plane of the illumination optical device. Illumination pupil forming means for forming;
Illumination optics comprising: area changing means for changing the position and size of the light intensity distribution located in the plurality of peripheral areas independently of the light intensity distribution located in the central area. apparatus. The illumination pupil forming unit converts the incident light beam into a central light beam corresponding to the central region and a plurality of peripheral light beams respectively corresponding to the plurality of peripheral regions and makes the light beam conversion element enter the region changing unit. The illumination optical apparatus according to claim 1, comprising: The region changing means includes a first prism having a refracting surface having a concave cross section, and a second prism having a refracting surface having a convex cross section formed substantially complementary to the refractive surface of the concave section of the first prism. Have
An interval between the first prism and the second prism is configured to be variable,
3. The illumination optical apparatus according to claim 1, wherein the refractive surface has a planar center portion substantially orthogonal to the optical axis. The illumination optical apparatus according to claim 3, wherein the refractive surface includes the central portion and a peripheral cone portion corresponding to a side surface of a cone centered on the optical axis. The illumination optical device according to claim 4, wherein the peripheral cone portion includes one peripheral cone portion corresponding to a side surface of one cone having the optical axis as a center. The peripheral cone includes an inner peripheral cone corresponding to a side surface of the first cone centered on the optical axis, and a second cone centered on the optical axis and having a smaller apex angle than the first cone. The illumination optical device according to claim 4, further comprising an outer peripheral cone corresponding to a side surface of the body. 7. The area changing unit according to claim 3, wherein the region changing unit includes a plurality of exchangeable pairs of the first prism and the second prism, and the area of the central portion is different for each set. The illumination optical device according to claim 1. In the illumination optical device that illuminates the illuminated surface,
Illumination pupil forming means for forming an illumination pupil distribution having a light intensity distribution located in the first region and a light intensity distribution located in the second region on or near the pupil plane of the illumination optical device;
An illumination optical apparatus comprising: a polarization setting unit configured to set a light beam passing through the first region to a non-polarized state and set a light beam passing through the second region to a polarization state. The first region has a central region including an optical axis,
The illumination optical apparatus according to claim 8, wherein the second region has a peripheral region spaced from the optical axis. The second region has two peripheral regions arranged substantially symmetrically with respect to the optical axis along the first direction;
The polarization setting unit sets a polarization state of a light beam passing through the two peripheral regions to a linear polarization state having a polarization plane in a direction substantially orthogonal to the first direction. Illumination optical device. The second region has four peripheral regions arranged at the positions of the vertices of a rectangular quadrilateral having a side along the first direction and a side along the second direction substantially orthogonal to the first direction. Have
The polarization setting means sets a polarization state of a light beam passing through the four peripheral regions to a linear polarization state having a polarization plane in the first direction or the second direction. Illumination optical device. The second region has four peripheral regions arranged at the positions of the vertices of a rectangular quadrilateral having a side along the first direction and a side along the second direction substantially orthogonal to the first direction. Have
The polarization setting means sets a polarization state of a light beam passing through the four peripheral regions to a linear polarization state having a polarization plane in a direction that forms an angle of approximately 45 degrees with the first direction or the second direction. The illumination optical apparatus according to claim 9. The polarization setting means is configured to change a polarization state of a light beam passing through one pair of peripheral regions facing each other with the optical axis between the four peripheral regions at an angle of approximately 45 degrees with the first direction. The linear polarization state having the polarization plane in three directions is set, and the polarization state of the light beam passing through the other pair of peripheral regions facing each other across the optical axis is at an angle of approximately 45 degrees with the first direction. 13. The illumination optical apparatus according to claim 12, wherein the illumination optical apparatus is set to a linear polarization state having a polarization plane in a fourth direction substantially orthogonal to the third direction. The second region is arranged in four positions arranged at the vertices of each rectangular first quadrilateral having a side along the first direction and a side along the second direction substantially orthogonal to the first direction. An inner peripheral region, a side along the first direction and a side along the second direction, and arranged at the position of each vertex of a rectangular second quadrangle surrounding the first quadrangle Four outer peripheral regions,
The polarization setting means sets a polarization state of a light beam passing through the four inner peripheral regions to a linear polarization state having a polarization plane in the first direction or the second direction, and sets the four outer peripheral regions. The illumination optical apparatus according to claim 9, wherein a polarization state of a light beam passing therethrough is set to a linear polarization state having a polarization plane in the second direction or the first direction. The second region is arranged in four positions arranged at the vertices of each rectangular first quadrilateral having a side along the first direction and a side along the second direction substantially orthogonal to the first direction. An inner peripheral region, a side along the first direction and a side along the second direction, and arranged at the position of each vertex of a rectangular second quadrangle surrounding the first quadrangle Four outer peripheral regions,
The polarization setting means changes the polarization state of the light beam passing through the four inner peripheral regions and the four outer peripheral regions into a linear polarization state having a polarization plane in a direction that forms an angle of approximately 45 degrees with the first direction. The illumination optical apparatus according to claim 9, wherein the illumination optical apparatus is set. 16. The depolarization element according to claim 8, wherein the polarization setting unit includes a depolarizing element for depolarizing a linearly polarized light beam toward the first region as necessary. Illumination optical device. The said polarization setting means has a phase member for changing the polarization plane of the linearly-polarized light beam which goes to the said 2nd area | region as needed, The any one of Claim 8 thru | or 16 characterized by the above-mentioned. Illumination optical device. 18. The polarization setting means further comprises a second phase member for changing incident elliptically polarized light into linearly polarized light having a polarization plane in a predetermined direction. Illumination optical device. 19. The apparatus according to claim 9, further comprising an area changing unit that changes the positions and sizes of the plurality of peripheral areas independently of the central area. Illumination optical device. The illumination pupil forming unit includes a light beam conversion element for converting an incident light beam into a central light beam directed to the central region and a plurality of peripheral light beams directed to the plurality of peripheral regions and to enter the region changing unit. The illumination optical apparatus according to claim 19. In the illumination optical device that illuminates the illuminated surface,
Illumination pupil forming means for forming an illumination pupil distribution having a light intensity distribution located in the first region and a light intensity distribution located in the second region on or near the pupil plane of the illumination optical device;
An illumination optical apparatus, comprising: polarization state changing means for changing a polarization state of the light beam passing through the second region independently of a polarization state of the light beam passing through the first region. The first region has a central region including an optical axis,
The illumination optical apparatus according to claim 21, wherein the second region has a peripheral region spaced from the optical axis. 23. The illumination optical apparatus according to claim 21, wherein the polarization state changing unit changes a state of a light beam passing through the first region between a non-polarized state and a linearly polarized state. The polarization state changing means changes the state of the light beam passing through the second region between two linear polarization states having polarization planes in different directions. The illumination optical device according to Item. 25. The depolarization element according to claim 21, wherein the polarization state changing unit includes a depolarizing element for depolarizing a linearly polarized light beam toward the first region as necessary. Illumination optical device. 26. The illumination optical apparatus according to claim 25, wherein the depolarizing element is configured to be detachable with respect to an optical path. The polarization state changing unit includes a phase member for changing a polarization plane of a linearly polarized light beam directed to the second region as necessary. 27. Illumination optical device. 28. The second phase member according to claim 25, further comprising a second phase member for changing the incident elliptically polarized light into linearly polarized light having a polarization plane in a predetermined direction. The illumination optical device according to any one of the above. 29. The apparatus according to any one of claims 22 to 28, further comprising region changing means for changing the positions and sizes of the plurality of peripheral regions independently of the central region. Illumination optical device. The illumination pupil forming unit includes a light beam conversion element for converting an incident light beam into a central light beam directed to the central region and a plurality of peripheral light beams directed to the plurality of peripheral regions and to be incident on the region changing unit. 30. The illumination optical apparatus according to claim 29. In the illumination optical device that illuminates the illuminated surface,
Illumination pupil forming means for forming a light intensity distribution located in a ring-shaped region having the optical axis substantially in the center on or near the pupil plane of the illumination optical device,
The ring-shaped region has a plurality of regions along a circumferential direction of a circle substantially centered on the optical axis,
The polarization state of a plurality of light fluxes passing through each of the plurality of regions of the annular zone is set to a linear polarization state having a polarization plane along a direction substantially in contact with the circle at substantially the center of each of the plurality of regions. An illumination optical apparatus, further comprising polarization setting means for performing The polarization setting means has a plurality of phase members arranged so as to correspond to the plurality of regions, and each phase member changes a polarization plane of incident linearly polarized light as required. The illumination optical apparatus according to claim 31. 33. An exposure apparatus comprising the illumination optical apparatus according to any one of claims 1 to 32 for illuminating a mask, and exposing a pattern of the mask onto a photosensitive substrate. A projection optical system for forming an image of the mask pattern on the photosensitive substrate;
34. The exposure apparatus according to claim 33, wherein a pupil plane of the illumination optical apparatus is positioned substantially conjugate with a pupil position of the projection optical system. An illumination step of illuminating the mask using the illumination optical apparatus according to any one of claims 1 to 32;
And an exposure step of exposing the pattern of the mask onto a photosensitive substrate. The exposure step includes a projection step of forming an image of the mask pattern on the photosensitive substrate using a projection optical system,
36. The exposure method according to claim 35, wherein a pupil plane of the illumination optical apparatus is positioned substantially conjugate with a pupil position of the projection optical system.

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